The invention relates to a workpiece or a machine part of compound steel, comprising a support jacket having at least one longitudinal recess and whose preferred shape is cylindrical over at least one portion of its exterior surface, wherein the recess(es) are furnished with at least one attrition-resistant and/or corrosion-resistant lining over the circumference, and a metal bond or connection with the support jacket is produced by pressing, forging, rolling, or the like.
Due to internal pressures ranging from 1000 to 2000 bar, the frequently high level of corrosion, and not least of all due to the fillers used, e.g. in plastics processing, compound steel workpieces and machine parts of this type are subject to high levels of attrition. It has been shown that certain filling materials, e.g. fiberglass, can reduce the service life of these parts 1/10 of their original value. Inasmuch as the maximum admissible play between screw and cylinder in injection molding machines is 0.25 mm, it is possible to estimate the significance of the attrition factor; machine manufacturers consequently have taken great efforts to resolve this technical problem.